AFC Telford United defender Dan Preston will be suspended for five more games following his red card against Luton Town last Saturday.
Both teams were charged with failing to control players following their fiery Blue Square Bet Premier encounter.
Preston, Bucks team-mate Jake Reid and Luton's Ronnie Henry were all sent off, while Preston and Luton's Jon Shaw both admitted charges of violent conduct.
The 20-year-old Preston has already served one game of his ban.
Luton striker Shaw accepted an automatic three-match suspension but Preston wanted a personal hearing, in an attempt to avoid a six-match ban.
A Bucks statement read: "We have not yet been informed of the reasons why the appeal was dismissed and will make no further comment on the matter."
The clubs have until 3 September to submit a response to the charges of failing to control their players.